The present invention relates to valved closures for containers used in packaging liquids, powders and more particularly pastes and like substances. Although the invention is useful as a closure and dispensing means for glass, plastic or metallic containers, it is particularly well-adapted to collapsible tubes of the kind used for packaging paste products such as toothpaste, hand and body lotions, shaving cream, paint pigments, paste food, cement and glue, and like material.
Such collapsible tubes, generally made of a soft metal and sometimes of thin pliable plastic, are designed to permit the contents to be ejected in desired quantities upon manual pressure being exerted on the wall of the tube. They are provided with a neck through which the contents is ejected, and the neck is generally peripherally threaded for cooperation with a threaded closure cap. When it is desired to remove a portion of the contents from the tube, the cap is removed, a desired portion of the contents is expelled and the remainder of the contents in the tube is sealed from the ambiant by returning the cap to the threaded neck portion.
Although collapsible tubes with removable caps present many inconveniences, they have been generally accepted for many years as packaging and dispensing means for diverse products. A first inconvenience is that the threaded cap is often difficult to remove from the threaded neck portion, especially when the collapsible tube contains a material tending to dry and harden when exposed to the atmosphere. In view of the relative elasticity of the collapsible tube wall, it is often difficult to dispense a measured amount of the material contained in the tube, and the surplus amount of material must be wiped out from the neck aperture and from the neck thread, if it is desired to avoid excessive smearing and possibly the cap remaining stuck on the neck as a result of the material smearing the thread becoming dry and hardened. In addition, the material oozing from the neck to around the bottom of the cap presents a somewhat messy appearance and may result in unsanitary conditions. The cap may be easily dropped and lost, the replacement caps are not easily obtainable. When the collapsible tube is stored without the cap in position over the neck, the contents may ooze out from the tube or, if the contents of the tube consist of an air-hardenable material the contents of the tube in or near the neck portion becomes dry and hard to the point that it may become impossible to squeeze further material from the tube.
Dispensing spouts for containers have been proposed in the past to remedy the inconveniences of removable cap closures for containers. Examples of such structures may consist for example, of an orientable spout, as disclosed in U.S. Pat. No. 2,866,580 which, in one position, places the interior of the container in communication with the ambient by registering with an appropriate dispensing aperture, and which, in a second position out of alignment with the aperture, isolates the interior from the ambient. Particularly when dispensing pasty material such an arrangement allows some of the material to remain in the spout and to dry out, although it is apparently perfectly suitable for dispensing liquids, especially liquids that are prone to evaporation such as lighter fluid and the like.
Other devices have been designed having a rotatable ball valve disposed in the neck of the container, as disclosed in U.S. Pat. Nos. 1,960,393 and 2,790,583, for example, the ball being provided with a passageway placing the interior of the container in communication with the ambiant in one position and isolating the interior from the ambiant in a second position wherein the passageway is engaged with a wall of the recess holding the ball. As the ball is elastically retained in a partially spherical socket, the use of too much pressure applied to the collapsible tube may expell the ball from its seat. If excessive pressure is externally applied on the ball, or if the container is dropped and the ball hits the ground, the ball may be pushed into the tube with the accompanying result that the closure becomes inoperable.
Other arrangements for dispensing closures which have been proposed, as disclosed in U.S. Pat. Nos. 1,598,434 and 2,534,139, for example, consist of an apertured rotatable outer sleeve surrounding an apertured inner sleeve. When the outer sleeve is rotated to a position matching the apertures, material may be dispensed from the container. The container is closed by rotating the outer sleeve to a position removing the apertures from registry. Such an arrangement presents the inconvenience that it generally necessitates the use of both hands for operation. The outer sleeve is provided with an enlarged diameter knurled portion which interferes with neat dispensing of the material, and some amount of the material remains in the outer sleeve aperture which results in unsanitary conditions and, after the material becomes dry and hard, operation of the closure becomes difficult.